Metallic ferromagnetism in the Hubbard model: A rigorous example

Akinori Tanaka; Hal Tasaki

doi:10.1103/physrevlett.98.116402

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Metallic ferromagnetism in the Hubbard model: A rigorous example

Akinori Tanaka·Hal Tasaki

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Abstract

We present the first rigorous example of the Hubbard model in any dimensions which exhibits metallic ferromagnetism. The model is a genuine Hubbard model with short-range hopping and on-site Coulomb repulsion, and has multi single-electron bands. In the limit where the band gap and the Coulomb repulsion become infinite, we prove that the ground states are completely ferromagnetic and at the same time conducting.

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Akinori Tanaka, Hal Tasaki. 2007-02-03. Metallic ferromagnetism in the Hubbard model: A rigorous example. https://doi.org/10.1103/physrevlett.98.116402

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